Fire-resistant sealing plug



FIG. 1 is a perspective view of a fire-resistant sealing plug showing my new design; and,

FIG. 2 is a front elevational view of the fire resistant sealing plug of FIG. 1.

The subject matter shown in broken lines is for illustrative purposes only and forms no part of the claimed design. The rear view, top view and bottom view (all not shown) form no part of the claimed design. 

The ornamental design for a fire-resistant sealing plug, as shown and described. 